Brief Answer:
Highly unlikely to be pregnant.

Detailed Answer:
Hello,

Welcome to Ask A Doctor Service.

I have gone through your query carefully and understand your concern.]

First let me get some physiological processes out of the way.

If your menstrual cycles are regular ( 28 days between each cycle ), then your ovaries will release the ovum (egg) on the 14th day of the cycle.

The 14 days is fixed, but counted backwards from the date of having your period, so if your cycles are 35 days long each time, then ovulation would happen around the 21st day.

For conception to happen, sexual intercourse must happen about 3 days prior to 2 days after ovulation, because sperms can survive for a few days in the female genital tract but the ovum can not survive for more than 2 days if fertilisation does not occur.

So coming back to your situation, you had your period on 15, and had intercourse on 21st which is 6 days after the beginning of the menstruation.

By then your uterus will not be ready to receive the fertilised egg (somehow even if the ovum gets fertilised).

Secondly, the follicles in the ovary would be still very small and not mature enough to release the egg. It would take another week for the ovum to be released.

Hence the chances of getting pregnant are very very remote.

The milky white discharge if associated with itching or burning sensation could be due to infection following sexual intercourse.

If there is no discomfort associated with white discharge, then it could just be the normal vaginal secretions.

Please visit your gynecologist to check if you have a vaginal infection.

I hope this answers your question.

Please feel free to ask me if you have any doubts.

Best regards

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